The invention relates to a machine tool for machining a rod-shaped workpiece, and, in particular, to a machine tool having a traveling column, to which a tool spindle rotatable about a spindle axis is fastened.
From DE 199 19 647 A1, a traveling-column machine is known, on the machine bed of which a workholding fixture for a workpiece is arranged. The workholding fixture is capable of swiveling about a horizontal axis, so that both a longitudinal side and an end face opposite the clamping point of a workpiece clamped therein can be machined by a tool which is accommodated in a tool spindle fastened to the traveling column. In order to also be able to machine the sixth workpiece side, a type of robot arm (manipulator) is provided, this robot arm being swivelable about a vertical axis and having a gripper. After the completion of the machining of the five sides of the workpiece which are accessible first of all, the gripper takes the workpiece out of the workholding fixture. The robot arm is then swiveled by 90° in the horizontal and by 180° about its longitudinal axis and the gripper is put into a clamping station. The clamping station holds and fixes the gripper and, thus, the workpiece which is still accommodated therein in a precise position, so that the workpiece can now also be machined on its sixth side by the tool.
It is a disadvantage of this known machine tool that either only relatively short workpieces in the workholding fixture can be swiveled into a vertical position in order to permit a machining of the free end face, or a large swivel space has to be provided, which allows a swiveling of longer workpieces, too.